BT DUET TELEPHONE


Duet 20
Gondola style corded telephone replaced by the Duet 210.

Key Features:

  • Tone dialling only
  • Time break recall only
  • Call indicator light
  • Wall mountable
  • Call Waiting
  • Redial button
  • LCD display
  • Mute
  • Loudspeaker
  • Last number redial
  • Recall
  • REN - 1

Colour: Chalk White
 

Duet 50


 

The Duet 50 is similar in design to the 100 but without LCD and a reduced facility range.  Facilities are as follows:-

  • Pulse/Tone switchable
  • 10 memories (up to 16 digits in length)
  • Last Number Redial (24 digits)
  • Ringer on/off switch
  • Switchable between pulse dialling or tone dialling with time-break recall only
  • Wall mountable

 

Duet 60
Corded gondola style telephone with LCD display. 

Key Features:

  • Tone dialling only
  • Time break recall only
  • Caller Display
  • 99 number calls list
  • 13 number memory store

  • Call Waiting

  • Call timer

  • Ringer on/off

  • Mute

  • 1571 Message Waiting

  • Hearing aid compatible

  • Wall mountable

Colour: Ink Black and Chalk White

 

Duet 80
The Duet 80 (pictured to the right) is similar in design to the Duet 200 but without LCD and a reduced facility range.

Key Features:

  • Pulse/Tone switchable
  • 10 number memory
  • Last number redial
  • Adjustable ringer - high/low/off

Colour: White

 

Duet 100
The slim style Duet 100 comprises a handset and base unit with the keys and LCD housed in the handset.

Key Features:

  • 13 memories (up to 24 digits in length)
  • Liquid Crystal Display (10 digit)
  • Latching Secrecy Button (with LED)
  • Last Number Redial (24 digits)
  • Ringer Volume Control (Hi/Lo/Off)
  • Pause Facility
  • Switchable between pulse-earth, tone-earth and time-break recall
  • Wall mountable

Colours: Alpine White, Oatmeal, Gentian Blue, Peach and Baltic Green

Introduced 1992

Duet 200

The Duet 200 is a conventional two piece design but with LCD and facility keys housed in the handset rest.

Key Features:

  • 13 memories (up to 24 digits in length)
  • Liquid Crystal Display (10 digit)
  • Latching Secrecy Button (with LED)
  • Last Number Redial (24 digits)
  • Ringer Volume Control (Hi/Lo/Off)
  • Pause Facility
  • Switchable between pulse-earth, tone-earth and time-break recall



 

Duet 200 Plus
Ideally suited to the residential market, the Duet 200 Plus is a stylishly designed and affordable corded phone with LCD. A ringer volume control allows the user to select how loud the phone rings - perfect for the noisy household and the hard of hearing.

Key Features:

  • Pulse/Tone switchable

  • Earth/Time break recall selectable

  • LCD

  • Number of indirect memories - 12

  • Call timer

  • Last number redial

  • Ringer volume control

  • Mute button

  • Recall button

  • Memory without power - 5 mins

  • Time break recall

  • Tone dialling

  • REN - 1

 

Duet 210
The Duet 210 corded telephone is an affordable but elegant small gondola phone that is will sit on a desk or table or is wall mountable. It has a light that flashes when you have an incoming call. It is also fitted with an inductive coupler so it is hearing aid compatible.

No batteries or power supply unit are required with this product.

Key Features:

  • 10 number memory
  • Last number redial
  • LED call indicator
  • Hearing aid compatible
  • One standard ring tone
  • Mute facility
  • PBX compatible with PBX access code
  • Wall mountable
     


 

Duet 450
BT's lowest ever priced corded phone (as 2001). The Duet 450 comes in a range of colours and is wall mountable.

Key Features:

  • Number of direct memories - 3
  • Number of indirect memories - 10
  • Last number redial
  • Recall button
  • Ringer volume control
  • Mute button
  • Touchtone dialling
  • Time break recall
  • Tone dialling
  • REN - 1


 

Duet 450C
A simple to use phone with full alarm clock functions including a snooze feature.

Key Features:

  • 13 number memory

  • Clock features

  • Digital 12 hour clock with PM indicator

  • Green LED display

  • Snooze button

  • Alarm indicator

  • Alarm on/off button

  • Back-up battery provision

  • Night light

  • Hookswitch

  • Last number redial

  • 3 one-touch memory buttons

  • Night light

  • 10 quick dial memories

  • REN - 1

  • Recall

  • Ringer volume control

  • Secrecy button

Colour: White

 

Duet 500
Duet 500 was BT's lowest ever priced corded phone with LCD at the time.

Key Features:

  •  Visual ring indicator
  •  Last number redial
  •  Number of direct memories - 3
  • Number of indirect memories - 10
  • Recall button
  • Ringer volume control
  • Mute button
  • Wall mounted for additional security
  • Time break recall
  • Tone dialling
  • REN - 1

Colours: Alpine White and Dark Blue


 

 


Duet 550
The Duet 550 replaces the Duet 450 in the BT one piece corded gondola range. It has a range of features including a secrecy button for when privacy is required and it is also wall mountable.

Key Features:

  • Direct Memories - 3
  • Indirect Memories - 10
  • Recall button
  • Wall mounted for additional security
  • Ringer volume control
  • Visual ring indicator
  • Redial button
  • Full Modular Cordage
  • Secrecy + LED

Colour: Alpine White
 


Duet 600

The BT Duet 600 corded gondola phone is the replacement for the Duet 500. This telephone however comes with a three-line LCD and a visual ring indicator.

Key Features:

  • Direct Memories - 3
  • Indirect Memories - 10
  • 3 line LCD
  • Recall button
  • Ringer volume control
  • Visual ring indicator
  • Redial button
  • Full Modular Cordage
  • Secrecy + LED
  • Quickdial - 10
  • Call timer
  • Wall mounted for additional security

Colour: Alpine White

Duet 600 User Guide
 

Duet 700
The Duet 700 from BT is a fully featured, stylish gondola phone. It comes complete with Caller Display, a unique 2 sided backlit LCD, 50 calls list, 50 name and number memory and a flashing new calls indicator.

Key Features:

  • Recall button
  • Caller Display
  • Ringer volume control
  • 2 Sided backlit LCD
  • Visual ring indicator
  • Calls list - 50 calls
  • Redial button
  • Name and number memory
  • Secrecy + LED
  • 50 names
  • Wall mountable for additional security
  • Requires 3 x AA batteries

Colour: Alpine White

Batteries must be replaced within 10 minutes or the memory will be lost.
 



 

Additional Information

Originally made by Inventec

APPROVAL STATUS
Approved under Approval numbers:-
Duet 50: S/2981/3/P/502805
Duet 80: S/2981/3/P/502804
Duet 100: S/2981/3/M/502288
Duet 200: S/2981/3/M/502324

The Duet 100 and 200 is approved for use on DELs and PBXs in categories 1,3,5,7,9 & 11. Duet 50 and 80 is not approved for use on PBXS.

All telephones in the Duet range have a REN of 1 and are intended for use in normal Domestic/Residential locations. In addition Duet 100 and 200 may be connected to any approved PBX.

Approximate overall dimensions are:-
Duet 50 & 100: 220mm(long) x 65mm(wide) x 73mm(high), weight 554 grams.
Duet 80 & 200: 164mm(deep) x 225mm(wide - including handset) x 63mm(high), weight 524 grams.

Two 25mm x No. 8 pan-head wood screws and wall plugs are provided for wall mounted use via key-hole slots in the base of the Duet 50 & 100.

The Signalling switch of the Duet 100 or 200 should be set on installation according to the type of exchange/PBX it is used on, i.e.;

TB - for Digital or Modernised TXE4 exchanges and a minority of PBXs (i.e. for MF, Star Services and Timed Break Recall PBXS).
T - for the majority of modern PBXs (i.e. with MF signalling with Earth recall).
P - for unmodernised exchanges and older PBXS. (pulse signalling)

PARTS

Description  BT Item Code
Duet 50
Alpine White 870630
Oatmeal 870631
Duet 80
Alpine White 870633
Oatmeal 870634
Duet 100
Alpine White - 1992 877939
Oatmeal - 1992 877940
Gentian Blue - 1992 877941
Red Earth - 1992 870649
Ocean Green - February 1994 877944
Peach - June 1992
Baltic Green - June 1992
Duet 200
Alpine White - April 1992 877945
Oatmeal - April 1992 877946
Black - April 1992 877947
Red Earth - June 1992 877948
Marble Grey 877949
Duet 200 Plus (1997)  
Antique Red  
Black  
Midnight Blue  
Magnolia  
Green  
White  

LINE TESTING
Idle - Normal capacitor loop, additionally these telephones draw on-hook current (typically 10 micro Amps) to maintain stored/last number memory. This may give apparent 'Low Loop' line test conditions.
Seized - Normal press button telephone loop. The electronic keypad and transmission circuitry may give 'high resistance' tele-loop line test conditions as with other press button telephones.

ADDITIONAL INFORMATION
Signalling details:

MF signalling
All models, continuous tone whilst button is pressed.
Timed break recall, all models, approximately 90 ms.

Earth recall
Duet 100 and 200 only, continuous whilst recall button is pressed (to a maximum of 1.35 seconds).

Duet 100 and 200 from the serial numbers below will no longer support earth recall:-
DUET 100 From Serial No. 9433000000
DUET 200 From Serial No. 9429000000 

PBX Interworking:
Some facilities are not available when Duet 100 or 200 telephones are connected to a Renown or BT2+8. Duet 50 and 80 telephones are not suitable for connection to a Renown or BT2+8.

 


 
 
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Last revised: April 17, 2021

FM